Underground Concrete Cisterns
Advantages:
- Can be an economical underground storage solution for large volumes of water
- Provides a storage volume with a very long life
- Foundation or basement excavation can be expanded for cistern installation in order to take advantage of mobilization
- Provides load bearing capabilities which allow them to be installed under driveways and parking lots
- Provides a constant temperature of stored water year round
- Can be configured in any shape, depth, layout to custom installation by project
- Can neutralize the slightly acidic rainwater with the concrete walls
- Can be food grade, NSF approved for drinking water storage if a liner system is used inside the cistern
- Can be repaired if a crack develops
Disadvantages:
- This style of cistern can be very expensive at lower volumes of water storage
- Precast concrete cisterns are not readily available and may involve expensive shipping costs if cistern is desired
- Excavation for cistern and placement of the cistern requires heavy equipment and access can be difficult in some project sites
- Movement of soil can cause cracks in concrete cistern over time (best practice is to install liner inside tank)
- Sustainability-wise: Portland cement used to make concrete requires a lot of energy to manufacture
